fourth coat?

This is my first construction project. Framing was bad and hanging the drywall was bad. (Good judgement comes from experience, experience comes from poor judgement, poor judgement comes from lack of experience). So what chance did the mudding have?

After the tape I figured my only chance was to rip it down and start over, but I pressed on.
After the 2nd coat it looked better; I mean, its just a basement and some of the other walls are just blankets of insulation...
After the 3rd coat; it looked better, maybe with a fourth coat...

Assuming there is nothing sacred about 3 coats, do I just put on a fourth coat like the third, or do I sand first?

Advertisement

It's the thickness that counts, not the number of coats. I think you're supposed to keep the mud under 1/4" total thickness but I forgot where I read that. It's up to you whether to sand between coats. Many people just chip off high spots. With that many coats, go easy on smoothing with a wet sponge, if you're doing that, because the more you wet the mud the more you break the bond with the wall.

do as many coats as needed. 3 coats is the norm for regular new drywall. coating some bad butts can sometimes take 4-5 coats. If its really nasty i would either repair the wall/drywall before mudding. if that is easier said then done then i would tape it then mix up some thick sheetrock 20,45,90. and load the bad joint 1/4" thick. then skim it with my regular regular 2nd,3rd coat mud. 1/2" thick one coat? i think its possible unless you scoop the mud out and just slap it on.

i've skimmed out some nasty joints that were close to an inch. by the time im done its 8' wide and 6-7 coats later.and i've noticed on some premixed compound boxes that it says you can apply it up to a 1/4" thick. although you will get nasty bubbling. so lay it on thick with the powdered then do thin tight skims with the premix.